Agilex™ 5 ES Device Errata and User Guidelines

ID 825514
Date 12/09/2024
Public
Document Table of Contents

3.2.15. 2227007: PMU L1D_CACHE_REFILL_OUTER is inaccurate

Description

The L1D_CACHE_REFILL_OUTER PMU event 0x45 is inaccurate due to ignoring refills generated from a system cache. The L1D_CACHE_REFILL PMU event 0x3 should be the sum of PMU events L1D_CACHE_REFILL_INNER 0x44 and L1D_CACHE_REFILL_OUTER 0x45, however, due to the inaccuracy of L1D_CACHE_REFILL_OUTER 0x45 it is possible that this might not be the case.

Note: L1D_CACHE_REFILL PMU event 0x3 does accurately count all L1D cache refills, including refills from a system cache.

Conditions

The L2 inner cache is allocated with data transferred from a system cache.

Impact

When the previous condition is met, the L1D_CACHE_REFILL_OUTER PMU event 0x45 does not increment properly.

Workaround

The correct value of L1D_CACHE_REFILL_OUTER PMU event 0x45 can be calculated by subtracting the value of L1D_CACHE_REFILL_INNER PMU event 0x44 from L1D_CACHE_REFILL PMU event 0x3.

Category

Category C